No passports, no borders, no testimonies of abuse and tragedy, no rescue boats needed. It is a wonder of nature to see the nesting birds, resident and visiting species together; noise and chaos, but they manage to get along.

If this irrational, punishing referendum is perceived to be about migration, the Outers might win. If it is about economics then there is no sound argument for leaving the EU.

Invest in what matters, Mr Cameron, then we wouldn’t be falling over one another to condemn immigration for all our woes. Immigrants are taking the brunt of our pent-up grievances – lack of affordable housing, a patchy education system, the regional divide, poor infrastructure, and anger at political elites and underfunded public services.

Should the Leave camp prevail, I want to thank the immigrants here who have set up businesses, provided skilled and unskilled labour, worked hard and paid the taxes (yes, their net contribution is positive) that will eventually pay my pension.

How daft to cut ourselves off from our own continent, to not look beyond our shores. No island should be an island these days. International cooperation on an unprecedented scale is needed to address challenges like climate change, decreasing biodiversity and increasing numbers of refugees, none of which respect borders.

Our pared-down border patrols would be alone without the bulwark of Europe. May we be spared the awful sight of bodies washing up on our beaches.

Immigration is the red herring of the referendum debate, it is feeding a xenophobia antithetical to the liberal tolerance that has long defined Britishness. To discard EU membership in order to express a hostility to immigration is economically self-defeating. The EU’s main advantage is as a large and wealthy single market governed by the rule of law in a lawless world.

Did you know Europe is the most peaceful of the nine geographical regions on the latest Global Peace Index? Humans know how to waste money. There has been more spending on violence than peace; the price tag on violence added up to $13.6 trillion in 2015, or 13.3% of gross world product. Investments in peacekeeping and peacebuilding, in contrast, totalled $15 billion.

Seagulls aren’t on the endangered species list, I thought with slight regret as two fat herring gulls dive-bombed me. My decades-long run of good health has to peter out eventually; one day I will be wheeled into ER with pecked-out eyes and rusted limbs. The migration argument works because it builds on everyday gripes such as dysfunctional hospitals hit by government austerity policies.

We need more, not less, healthcare collaboration between EU countries and more access to EU funds for NHS projects. Skilled workers from Europe make up around 10% of NHS doctors and 4% of nurses.

Some of them would leave the UK in the event of Brexit. The NHS has neither the capacity nor the money to survive this. The Institute for Fiscal Studies said leaving the EU would not, as Brexit claims, leave more money to spend on the NHS. Rather it would leave us spending less on public services, or taxing more, or borrowing more.

Further down the coast is Sunderland, a city ranked as among the most Eurosceptic in Britain. This is despite the north-east of England receiving large amounts of European funding – Sunderland has received more than £23m of direct investment from Europe since 2007 – and its buoyant car industry exporting most of its vehicles to the EU.

Brexiteers may hope for a bespoke deal for Britain that gives access to the single market without EU rules, free movement of people or budget contributions. Frankly, this is delusional.

As the sand squished between my toes while heading back to my van, I thanked European legislation for improving the 95% of British beaches now clean enough to wade across.

One last glance back across the water. From the Middle Ages Europe has prospered on the open exchange of technologies, goods and ideas.

We are a global crossroad. Britishness is from many peoples and cultures, and may it remain so.